1. Field of the Invention
The present invention relates to lumbar supports, particularly for use in folding seats of vehicles.
2. Related Art
Fold-down rear seats are a very popular feature in vehicles. The folding of seats to make cargo space available is preferable to having to remove seats completely. To maximize the amount of cargo space available upon folding of the seats, it is preferable to have the seats fold into a very thin profile form. One way to minimize the folded profile of a seat is to reduce the amount of cushioning in the seat. However, at the same time consumers also want the unfolded seats to be comfortable. Thus there is a balance between maintaining seat comfort versus the ability to fold the seat into the most compact form possible.
Further complicating the issue is the consumers' desire to have advanced comfort features such as ergonomic support devices on all of the seats of the vehicle. Many seats, even in the rear passenger positions, contain ergonomic support devices embedded therein to promote passenger comfort. Such devices, for example lumbar supports, typically have three-dimensional forms that support different parts of the body. These three-dimensional forms, however, may limit the degree to which seats containing the ergonomic devices can fold up.
Although some systems have been designed which promote the flattening of ergonomic support devices upon folding of a seat, many such systems are heavy and can be noisy during use, and are complicated and costly to assemble. Furthermore, due to the high spring rate of the springs incorporated into many of these designs, some systems can require a large amount of force to fold the seat down. The higher spring rate requires the use of heavier gauge components, which of course weigh more, and places more stress on the system's components over the long term.
The purpose of the present invention is to provide back support for a seat occupant, plus fold to a very thin profile when the seat is in the stowed position, while solving one or more of the above-identified problems.